Here is the question: sodium hydride reacts with excess water to produce aqueous
ID: 684327 • Letter: H
Question
Here is the question:sodium hydride reacts with excess water to produce aqueous sodiumhydroxide and hydrogen gas:
NaH(s)+H2O-->NaOH(aq)+H2(g)
A sample of NaH weighing ________g will produce 982mL of gas at28.0 C adn 765 torr, when the hydrogen is collected over water. Thevapor pressure of water at this temperature is 28 torr.
Note: You may have to consider that all the pressure stated abovedoes not solely belong to the hydrogen gas.
Here is my Homework:
n=PV/RT
P=1.01atm or 765torr
R=.0821
V=.982 L
T=301.15 K
(1.01atm H2)(.989L H2)/(.0821 Latm/mol L)(301.15k H2)=3638.08 molH2
3638.08 mol H2 = 3638.08 mol NaH
(3638.08 mol NaH)23.99771 g/mol NaH=87305.5887968
The assessment is saying this answer is incorrect can anyone tellme what I am doing wrong?
Explanation / Answer
Your math is incorrect (1.01atm H2)(.989L H2)/(.0821 Latm/molL)(301.15k H2)=3638.08 mol H2 it should be close to .4. Considerthat you are solving a problem that is close to stp measures and itwould be a clear indicaotor that the numbers are off.